The present application relates to a communication device, a communication method, a reader/writer, and a communication system. More specifically, the present application relates to a technique of performing readout or write of data with respect to a communication device from a reader/writer.
In a communication system such as an IC card system and the like of the related art, mutual authentication is performed for every communication session to generate a cipher key in order for the reader/writer to perform cipher communication and securely perform readout/write of data of the communication device (see e.g., Japanese Patent Application Laid-Open No. 2005-27338 and Japanese Patent Application Laid-Open No. 10-20780). According to such method, authentication is performed by generating a random number by a random number generation means of each of first and second information processing devices, replacing that in which the random number is encrypted using the key set in advance, and determining whether or not it can be correctly decrypted.
[Patent Document 1] Japanese Patent Application Laid-Open No. 2005-27338
[Patent Document 2] Japanese Patent Application Laid-Open No. 10-20780